azo group
Học thuậtThân thiện
Definition
- Noun:
- A bivalent chemical group: The
azo grouprefers to the bivalent functional group in chemistry with the structure -N=N-. This group is characterized by two nitrogen atoms connected by a double bond. It is united to (attached to) two hydrocarbon groups or other organic radicals, one on each nitrogen atom.
Usage
- The is a fundamental structural unit in a class of compounds called azo compounds.
- These compounds are widely used as dyes, pigments, and indicators due to the color imparted by the .
- In chemical nomenclature, the presence of an is indicated by the prefix "azo-" or the suffix "-azo".
Examples
- Noun:
- The vibrant red color of the fabric is due to an
azo groupin the dye molecule. - Azobenzene is a simple compound containing an
azo grouplinking two phenyl rings. - Chemists study the reactivity of the
azo groupin various synthetic applications.
Advanced Usage
- "Azo coupling": A key chemical reaction where a diazonium salt reacts with another aromatic compound to form an azo compound, creating a new .
- Azo coupling is an electrophilic substitution reaction used to synthesize dyes.
- "Azo dye": Any synthetic dye whose molecules contain one or more .
- Many
azo dyesare used in the textile, food, and cosmetic industries.
Variants and Related Words
- Azo compound (n): Any organic compound bearing the functional group R-N=N-R', where R and R' are usually aryl groups.
- Methyl orange is a common azo compound used as a pH indicator.
- Azobenzene (n): The prototypical aromatic azo compound with the formula C₆H₅-N=N-C₆H₅.
- Azobenzene can exist in cis and trans isomeric forms.
- Diazo (adj): Relating to or containing the group -N₂⁺ or =N₂. Diazo compounds are precursors to azo compounds.
- Diazonium salts are crucial intermediates in azo dye synthesis.
Synonyms
- Diimide (n): While technically H-N=N-H, the term sometimes refers to the -N=N- moiety in a general sense, though "azo group" is the standard term for the substituted version in organic chemistry.
- -N=N- group: A direct structural synonym.
Related Phrases and Concepts
- Azo reduction: The cleavage of the -N=N- bond, often by reducing agents, which is an important degradation pathway for azo dyes.
- Intestinal bacteria can catalyze the azo reduction of some food colorings.
- Azo initiator: A type of compound containing an used as a source of free radicals in polymer chemistry.
- AIBN (azobisisobutyronitrile) is a common azo initiator for radical polymerizations.
Noun
- the bivalent group -N=N- united to two hydrocarbon groups